Thermostatic switch



July 1, 1952 F. REINGRUBER ETAL 2,602,128

THERMOSTATIC SWITCH Original Filed Oct. 26, 1945 fllllllllllllllllflz:

::: gggllV////// Patented July 1, 1952 UNITED ys'lliras PATENT OFFICE THERMQSTATIC SWITCH Frank Reingruber, Yonkers, and Joseph Reingruber, Astoria, N. Y.

Original application October 26, 1945, Serial No.

624,674; now Patent No. 2,584,924, dated Feb'- ruary'5,'.19 52'. Divided and this application January-'591952, Serial No; 265,145

4Clal ms.

. frhisinvention relates to thermostats and more particularly to that typein which is employed two metals of dissimilar heat expansion characteristicto actuate azcontrol. whether an electric switch. relay valve-or the like. and is a division of our applicationSez-ialNo624,674, iiled October 26, 1945, PatentgNo. 2,584,924, granted Feb. 5. 1952. f

-Our invention contemplates :the vprovision of a comparatively sensitive f thermostat so designed and constructed that the-relatively small movementof the expandingsmetal is translated into a larger, multiplied or magnied movement of the control operating element and therefore provides a thermostatthat jreacts4 rapidly to relatively Small changesin'temperature.

Our invention further contemplates a thermostat of such constructionthatit may be readily applied in direct contact with the device to the temperature of which the thermostat is designed to react, and thereby one adapted to quickly react to relatively small changes in temperature thereof, thereby increasing the sensitivity of regulation and limiting the tendency of the device to overshoot thetemperature for which the thermostat is set.

Our invention still further contemplates the provision of a thermostat which is simple and rugged in construction, self-contained in a casing that may be conveniently applied as a unit to the article, the temperature of which is to be regulated.

Our invention also contemplates the provision of such a thermostatic unit that is relatively small in size and compact, reliable in operation and readily adjustable.

Other and further objects and advantages of the present invention and the uses to which it may be put, as well as the devices to which it may be applied, will be clear from the description which follows and the drawing appended thereto. in which:

Fig. l is a part sectional plan view of a thermostat unit according to our invention;

Fig. 2 is a longitudinal sectional view of the same on substantially the plane of line 2-2 of Fig. 1.

Referring now to the drawing. we have there illustrated a modication of our invention which is particularly adapted for use with a low temperature device, such as an electric heating pad.

In this modification the parts of the thermostat are housed in the casing H2, which itself serves as one electrode and therefore has secured to one side ||4 thereof the lead wire H6.

(Cl. D-137) The housing or casing ||2 constitutes theheat expanding. member of this modification andY is formed from a hollow-bar, tubeor rod'ofmaterial having a relatively high coeiiicient of expansion The legs 28 and 28 of the flexible'orcollapsible member 24 are secured in the interior of the casingY |`|2, as by welds |18, at the toes |08 and ||0 thereof,.to thev inside surface of wall i I4'.

The member 24 has a. relatively -lovv coefficient of expansion and is made of metal which is'an electrical conductor, such as. spring steel, and has secured to the platform-likeelement 30at its midpoint, the electrical contact |20 which serves as the movable terminal of the switch means.

On' the exterior ofthe casingl l2, at an opposite wall |22, we secure the contact `b`rack`etl|24lby any suitable means such as. the staples |"26;1which extend into the openingsl |28 in thecont'act bracket |24 and are peened over the insulating washers |30 to grip the various parts in place.

The contact bracket |24 is insulated from the casing ||2 by the mica sheets |30 and |32, held in place by the staples |26.

The contact bracket |24 is provided with a v tapped aperture in which the Calibrating screw |34, constituting the other fixed terminal of the switch means, is received so that it extends through the opening |36 in the wall |22, in contact with and against the electrical contact |20. Extending from the bracket |24, as an integral part thereof, we provide the terminal binding post |38 to which the lead wire |40 is secured.

The electrical circuit is therefore from the source (not shown) through the lead wire HB,

the casing I |2, contact |20, Calibrating screw |34,

bracket binding post |38 and through the lead wire |40 to the source.

The electrical contact |20, which is pulled away from the calibrating screw |34 upon heat expansion of the easing |2, returning in contact therewith upon contraction of the casing, constitutes together with the screw |34 the make and break switch which is controlled bythe expanding and positively moved members of the temperature responsive mechanism.

In the embodiment illustrated the expanding member constitutes the casing and the flexed member constitutes with the calibrating member, the make and break switch.

The relative dimensions of the various elements of the temperature responsive mechanism used with our invention will vary in practice.

The platform is preferably considerably smaller than the two legs and the angle Where they meet it or each other the toes should not be rounded It will be seen that we have provided a sensitive thermostat in which a relatively small.

linear movement of a heat expanded member is translated into a comparatively greater, multiplied or magnied movement of the member controlling the operation of the device.

It is further apparent that we have provided a thermostat in which the temperature responsive mechanism comprises a member'that readily exy pands or contracts under the miluence of changes in temperature to flex a second member which is spaced from it except at its ends, to thereby operate a control.

It is still further apparent that We have provided a simple, rugged, self-contained, compact and relatively small thermostat that is reliable in operation and readily adjustable.

While we have illustrated a specific embodiment of our invention, we do not intend to be limited to the specific details shown, but intend to claim our invention as broadly as the prior art and the scope of the appended claims permit.

What is claimed is:

1. A thermostat for making and breaking an electric current comprising a hollow bar of material having a relatively high coefcient of expansion and being a conductor of electricity. said bar constituting an electrode, a spring member arranged in the interior of the bar. said spring member being of a material having a relatively second inner wall of the low coefcient of expansion and being a conductor of electricity. said spring member bent at its center to form a platform spaced from a first inner wall of the bar opposite thereto and normally straight legs diverging from the platform to said rst inner wa said legs at their ends secured to the said rst inner wall and a second electrode extending through a second inner wall of the hollow bar and electrically insulated therefrom in normal contact with said platform. 2. The thermostat of claim 1. said second electrode having ascrew-threaded mounting on said hollow bar for selective adjustable positioning relative to the platform. 3. The( thermostat of claim 1 and including -an electrical contact on the platform intermediate the-platform and the second electrode and normally in contact therewith.

4. A thermostat for making and breaking an electric current comprising a hollow bar of material havinga relative highcoeicient of expansion, a` spring member'arranged in the interior of said bar. said spring member being of a material having a relatively low coefficient of expansion, said spring member bent at its'center to form a portion spaced from a. first inner-"wall of the bar opposite thereto and normally straight legs diverging from said portion to said first inner wall, said normallyl straight -legsbeing secured at their ends to said iirst-innerfwallland switch means operable' by said spring member and disposed between saidspacedcenter portion of said spring member and asecondinner-'wall of the hollow bar opposite'thereto. l

FRANK RZEINGRUBER. JOSEPH'REINGRUBER.

No references cited.. 

